# echo "scale=2;3/8" | bc

# echo "This is a sample text1" >temp.txt

# 查看文件内容
# cat temp.txt

# ls + 2> out.txt

# 文本重定向
# 
# #!/bin/bash
# cat<<EOF>log.txt
# LOG FILE HEADER
# This is a test loh file
# Function: System statistics
# EOF

# echo this is a test line >input.txt
# exec 3<input.txt
# cat<&3

# array_var[0]="test1"
# array_var[1]="test2"
# array_var[2]="test3"
# array_var[3]="test4"
# array_var[4]="test5"
# array_var[6]="test6"
# array_var[7]="test7"

# echo ${array_var[0]}

# echo ${array_var[*]}
# echo ${array_var[@]}
# echo ${#array_var[*]}
# 

# echo $(date +%s)


# echo $(date +%Y%m%d)
# 时间和星期几
# echo $(date +%H:%M:%S--%A)
# 星期 %A
# 月  %m
# 日  %d
# 年  %Y
# 小时 %I
# 分   %M
# 秒	   %S
# 纳秒  %N
# 


